1. Field of Invention
The present invention relates to an optical parts casing and a projector, and is also related to a projector that is widely utilized in a multimedia presentation in a conference, an academic conference, an exhibition, and so on.
2. Description of Related Art
The related art discloses a projector that emits a luminous flux from a light source to uniformize an intensity in an irradiated plane by an illumination optical system, then separates the luminous flux into three color lights of a red light, a green light, and a blue light by a color separation optical system, then modulates the color lights by an optical modulator device for every color light, then synthesizes the color lights by a color synthesis optical system, and then enlarges and projects a color image from a projection optical system.
The optical systems of such a related art projector have a plurality of optical parts respectively. For example, the illumination optical system has an integrator lens to divide the luminous flux emitted from the light source into a plurality of partial luminous fluxes and a condenser lens to converge the partial luminous fluxes. Also, the color synthesis optical system has a cross dichroic prism (color synthesis optical device).
These plural optical parts are housed in an optical parts casing referred to as a light guide which is made of metal, as shown in JP-A-2000-19645 (see FIG. 4), for example. Such a casing is constructed so that heat generated from respective optical parts is transferred to a bottom surface portion (outer surface portion) of the optical parts casing.
A method of cooling the bottom surface portion of the optical parts casing includes a method of introducing cooling air into an inside of the optical parts casing from the upper surface portion side of the optical parts casing to cool the optical modulator device, etc. and then feed this cooling air to a bottom surface portion to cool it.
Also, the related art includes a method of introducing the cooling air into the bottom surface portion side of the optical parts casing, and then introducing a part of the cooling air into an inside of the casing to cool the optical modulator device, etc., and also a part of the remaining air along the bottom surface portion to cool the bottom surface portion.